I use one of these amps a lot. I honestly have people ask me if it is a botique amp even with stock tubes and speaker. (But mine is broken in) The "Boost" switch is simply a midrange boost. It isn't a gain boost. I honestly don't use it. This amp REALLY likes pedals. I use a Bad Monkey boost pedal and a dirt box, usually a BBE Blacksmith. With channel switching I find the amp very usable. I also use a Weber Mini Mass attenuator to take the edge off. Before modding or worrying about that switch you might want to take some serious time dialing the amp in. In the same set I will use an LP, a Strat, and an electric resonator guitar from Fender clean to Marshall grind. If the Mid Boost truly sounds "bad" you might try swapping some preamp tubes around or seeing if another V22 has the same problem, as it hasn't been my experience. It just boosts the mids.